# Biophysics and Biomechanics of the Semicircular Canals

> **NIH NIH R01** · UTAH STATE HIGHER EDUCATION SYSTEM--UNIVERSITY OF UTAH · 2020 · $324,063

## Abstract

Summary. The present work seeks to advance quantitative understanding of angular motion sensation
by the semicircular canals, with specific attention to biophysics of transduction and signaling in crista
hair bundles. Experiments will be done using a new transgenic mouse strain developed in our
laboratory to image hair bundle deflection and calcium transients in stereocilia, in some cases through
the intact ampulla without disrupting the membranous labyrinth. The specific aims are motivated by
preliminary data localizing stimulus-evoked calcium puncta almost exclusively at the tipse of tall
stereocilia, data demonstrating upward movement of calcium puncta as the stimulus strength is
increased, and data suggesting ultrafast calcium signaling from the transduction site to the cell body.
Specific Aim 1 will localize mechano-electrical transduction channels in the bundle using physiological
stimulation, examine recruitment of channels as the stimulus strength is increased, and map the spatial
distribution of transduction across the surface of the epithelium. Specific Aim 2 will measure axial
movements of stimulus evoked calcium puncta in stereocilia, and examine potential micromechanical
and chemical-kinetic origins. Specific Aim 3 will investigate ultrafast calcium signaling from the site of
transduction at tips of hair bundles over a distance >40µm to the cell body.

## Key facts

- **NIH application ID:** 9933876
- **Project number:** 5R01DC006685-16
- **Recipient organization:** UTAH STATE HIGHER EDUCATION SYSTEM--UNIVERSITY OF UTAH
- **Principal Investigator:** RICHARD D RABBITT
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $324,063
- **Award type:** 5
- **Project period:** 2004-05-01 → 2023-06-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9933876

## Citation

> US National Institutes of Health, RePORTER application 9933876, Biophysics and Biomechanics of the Semicircular Canals (5R01DC006685-16). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/9933876. Licensed CC0.

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